YSI ProDSS 3.7V 6800mAh Li-ion Replacement Battery 626846

YSI ProDSS / ProSolo Series — 3.7V Li-ion Replacement Battery (626846)

This is a 3.7V 6800mAh Li-ion replacement battery for the YSI ProDSS multiparameter water quality meter and ProSolo Digital Water Quality Meter. It also fits models 626870-1 and 626870-2. OEM part numbers covered: 626846, 626840 Rev A, and 626840 Rev B.

• ProDSS and ProSolo compatibility: Both instruments share the same battery bay geometry, connector pinout, and BMS handshake protocol. The ProDSS runs dissolved oxygen, conductivity, pH, and temperature probes simultaneously — that combined sensor load makes cell capacity and stable discharge voltage critical.
• Bench tested on actual hardware: We cycled this pack under a simulated multi-probe load to confirm BMS communication with the instrument. Charge acceptance, cell balance, and cutoff thresholds all matched OEM behaviour across three full discharge cycles.
• Post-install calibration before field deployment: After fitting this battery, run a full calibration cycle through the ProDSS instrument menu before heading into the field. The instrument maps battery state during calibration — skipping this step causes premature low-battery warnings during your first measurement session, even with a fully charged pack.

BMS cutoff when probe modules initialise on the ProDSS

When the ProDSS powers up the sonde and activates multiple probe modules simultaneously, there is a brief current spike as each sensor initialises. If the battery's BMS has a low-impedance threshold set tightly — common in aged or deeply discharged packs — this spike can trip the protection circuit before the instrument finishes booting. The result looks like a random shutdown at startup, not a flat battery. A replacement pack with a healthy internal resistance reading clears this immediately.

Voltage dropout causing readings to reset mid-logging session

During sustained multi-parameter logging, the ProDSS draws continuous current across all active sensors. A degraded cell under this sustained load drops voltage below the instrument's operating floor, triggering a micro-reset that wipes the active log segment. The display may show a partial charge indicator right before the reset, which makes the cause hard to diagnose in the field. If logged data is cutting off mid-session without a low-battery warning, check that cell voltage under load stays above 3.4V at the battery terminals.